MVVM Pattern The document discusses the MVVM pattern, which is a variation of the MVC pattern introduced by the WPF team. It describes the key components of MVVM - the View, which represents the user interface and uses binding to subscribe to the ViewModel; the ViewModel, which is an abstraction of the View that acts as a connector between the View and Model; and the Model, which can be a data, domain, or service layer class. The MVVM pattern aims to remove logic from code-behind, allow independent development of the View and ViewModel, prevent duplicate code, and enable better testability. Several supporting libraries and frameworks for implementing MVVM are also listed.

1. MVVM PatternMahenderSenior Software EngineerUnited Health Group

2. Mahender SarangamHaving 5 years of experience on .NET Technologies. Working as a Senior Software Engineer in United Health Group (UHG India Information Service Ltd.). Worked with Big Firms like Deloitte Consulting & Wipro Technology. Got Technical Acquaintance on Technologies like C#, ASP.NET,AJAX, LINQ, Silverlight, WPF,WCF ,SQL Server, Team Foundation Server(TFS) and SharePoint Technology. MCTS Certified in Web Technologies.Blog : http://Msarangam.wordpress.com

3. Why Do need PatternEverything in code behind, is not a good idea

5. Why Do need PatternBasic Motivation of separation patternRemoving logic from Code behindInterchanging UI screensCreate Unit test case foe logic and UIDevelopers and Designers can work parallel.Model never needs to be changed to support changes to the viewNo duplicated code to update viewsSo what is MVVM ?Its variation of MVC patternJohn Gossman from WPF team Resources from external assembliesMartin Fowler's Presentation Model (PM) pattern

7. MVC & MVP Difference

9. DiagramView Knows VIEW MODELVIEW MODEL Knows MODELBUT VIEWMODEL does not know ViewViewView ModelModel

10. ViewRepresents the user interface that the user will see.

11. Can be a user control or Data Template

12. Keep the view as simple as possible.Uses Binding to “subscribe” to the ViewModelInterprets business data and state of ViewModel to the humanNothing but Presentation - XAMLNo or minimal code-behind

13. View ModelAn abstraction of View

14. Connector between View and Model